Manufacture of explosives.



No. 832,605. PATENTED OCT. 9, 1906.

G. W. GBNTIEU. MANUPAGTURE 0F BXPLOSIVES.

APPLICATION FILED MAY 10. 1906.

GEORGE W. GENTIEU, OF PEORIA, ILLINOIS.

MANUFACTURE OF EXPLOSIVES.

Specification of Letters Patent.

Patented Oct. 9, 1906.

Application filed May 10,1906. Serial No. 316,16-

To LZZ 'whom t may concern.-

Be it known that I, Gnonen W. GENTIEU, ,y a citizen of the United States, residing at `Peoria, in the county of Peoria and State of Illinois, have invented certain new and useful Improvements in the Manufacture of Explosives; and I do hereby declare that the following is a Jfull, clear, and exact description of the invention, which will 'enable others skilled in the art to which it appertains to make and use the same.

This invention has reference more particularly to the manufacture 'of-smokeless powder and my object is to provide a process for producing a smokeless explosive which is superior to those obtained-by the present processes.

Smokeless powder is .made chiefly trom `nitrocellulose, and [it is necessary, particularly in ordnance-powder, that it have a high degree of elasticity and toughness, so as to withstand the enormous pressure to which it is subjected in the powder-chamber during the firing of the charge. The rate of burning or rapidity of the explosion of the powder depends on `the size of the powder rains and the consequent burning-surface o the powder, the powder for the various sizes of guns being made in grains or sticks of suitable size.

to retard the explosion somewhat and generate gas just fast enough to exert a gradually- .'increasing pressure .on the projectile and gradually overcome the inertia of the projectileto be thrown by that particular gun. the grains or sticks of vexplosive are brittle or lack sucient toughness and elasticity to withstand the pressure to which they are subjected durin` the explosion of the charge, they are brdlren up into Jfragments by the pressure, thus increasing the burning-surface and `consequentlv the rapidity of the explosion.' lwhich resu ts in the transformation ot' the complete charge of' powder into gas before the inertia of the projectile is overcome and a large enough chamber iormed to accommodate the increased volume of gas and' creates a pressure which the walls of the rie are unable to withstand and bursts the gun or severely strains it.

Nitrocellulose, which, as has been hereinbefore suggested, is commonly used as the basisor smokeless powder, is made chiefly from cotton, as it is the purest and most satisfactory form of cellulose. The cotton consistsl of long tubular iibers or hollow ce lvl-vaud its hollow cellular structure is not destroyed or noticeably impaired by the process of nitrating, the tubular or hollow cellular str ucture being retained in the nitrocellulose. In the manufacture of powder from the nitrocellulose it is first pulped and thoroughly cleansed from acid, then dehydrated and colloded to such a consistency that it can be granulated or pressedinto sticks or pellets, and I have oundthat. if YtheV initial Vhollow cellular structure of the nitrocellulose is retained throughout the process of manufacture of smokeless powder therefrom a powder of great elasticity and' toughness is obtained.' The processes at present used in the manufacture of powder 4from nitrocellulose vare accompanied with more or less stirring and compressing action, which breaks up the hollow cellular structure of the nitrocellulose and results in the production' of a powder that is somewhat brittle and of insufficient elasticity and toughness to withstand the pressure of the explosion in the powderchamber.

In my process I provide a method of treatment of the nitrocellulose whereby it can be made into powder Without any stirring or compression, thus enabling me to retain the original cellular structure of the nitrocellulose and produce a powder of great elasticity and a high degree of toughness.

It is customary to coIloid the nitrocellul lose by mixing therewith alcohol and ethyl ether, neither of whichsaid liquids is in itself a solvent of nitrocellulose, but which when combined in lsuitable pro ortions form a solvent. The usual methold employed to mix the alcohol and ether with the nitrocellulose is to take nitrocellulose while wet from the cleansing or washing rocess, com ress the same in the cylinder o a press, an displace the Water remaining therein with alcohol by percolation, which reduces the nitrocellulose to the fornrof a hard compact block. Then take the alcoholized nitrocellulose from the cylinder of-the press, break it up into small particles, and mix with it a suitable quantity of ethyl ether to combine with the alcohol and form a solvent and gelatinize the nitrocellulose.

In my process, which relates more par- ICO ticularly to the method of mixing the ether l IIC process set out in an application for patent Jfor a dehydrating process, tiled by' me .April rated wall of the wringer.

t 5 cellulose saturated with alcohol.

o tight.

After thel material has been 27', 1906, Serial No. 314,010. In this process the wet nitrocellulose is introduced into the interior of a centrifugal wringer which is re volved at a high rate of speedand removes 5 the greater. percent. of the water from -the nitrocellulose and mats it against the perfo- Ater the surplus water has been removed from the nitrocellulose, alcohol or other suitable liquid is ro sprayed against the inner surface of the mass of nitrocellulose and as the wringer continues to revolve forces its way through the mass of nitrocellulose, thereby displacing the Water therein and leaving the nitro- I prefer the above process, as the cellular structure of the-nitrcellulose is not impaired thereby` and it retains its light porous condition and is better adapted to absorb the ether-vapor.A ro However, I do not confine myself to nitrocellulose treated by my foregoing process, but take nitrocellulose treated by any'suitable process which contains-the required amount of alcohol, place it in wire-mesh or other 5v suitable trays which will readily permit the entrance of ether-vaporto all parts of the nitrocellulose contained therein, and place the trays of nitrocellulose in a suitable receptacle or oven 4which is practically air- Ether is then introduced into a pan or other suitable container within .the oven and allowed-to evaporate or vaporize, the oven or receptacle being kept at a sufficient temperature (about 30O centigrade) to vapo- 5 rize the ether slowly without boiling. .The

nitrocellulose being wet with the proper per cent. of alcohol has the property of absorbing the ether-vapor very readily, which said vapor combines with the alcoholin the nitro- :v vcellulose and forms a solvent which gelatinizes the nitrocellulose. As is apparent, .by regulatinU the time and the amount ot' ether and a cohol used the nitrocellulose may be colloided to the required degree. colloided to the required degree it is taken from the oven and is ready to be pressed out into powder grains. Before being pressed into powder grains it may, however,. if desired, be run through a i screening-press or passedbetween a pair of rolls to remove any lumps. This` powder when dried will be found to be much tougher and less brittlethan that made by processes wherein the nitrocellulose is subjectedA to anyv stirring or compressing action, w1 ich is due to thefact that the original ollow 'cellularo structure of the nitrocellulose has not been destroyed or. noticeably impaired by my process.

In order that' my process may be more clearly understood, I have illustrated in the accompanying drawings 'an' apparatus such 'as I prefer to employ for carrying ou't my process, and I Will now describe my process -in connection therewith.

indicated by the arrow.

ualityv In said drawings, Figure l is a vertical longitudinal sectional view of the apparatus, and 2 is a vertical. cross-sectional view oiithe apparatus on the line a a of Fig. l looking as l is an oven or receptacle which is built with hollow walls, which are formed of the inner and outer casings 2 and 3, suitably spaced apart and held together by means of the rivets 4. The hollow walls 4of the oven or the space between the inner and outer casings 2 and 3 is designed to be lled with water to keep the oven at an even temperature, and there is prov-ided an inlet-pipe 5 at the top of the oven and an outlet-pipe 6 at the bottom of the oven, whereby hot water may be circulated through the hollow walls of the oven. For the purpose of indicating the temperature of the Water that is introduced intothe oven there is provided a thermometer 7, suitably fixed in the inlet-pipe 5.

In .the bottom of the oven or receptacle l is a shallow pan S, which is used to contain the ether which is evaporated in the process of gelatinizing the nitrocellulose, the ether being supplied to said pan from the tank 9 through the supply-pipe l() and\control valve 11. This ether-tank 9 is provided with any suitable means for illing the same, such as a 'common opening in the top thereof, closed by the threaded plug l2, and there is rovided at the side of the tank a graduated gage-glass 13, whereby the amount of ether used may be regulated.

-For the purpose of allowing access tothe interior of the oven one end thereof is provided with a large opening 14, which. is adapted to be closed practically air-tight by means of the door 15. This door maybe constructed to slide in ways 16 or otherwise adapted to be moved free of the opening 14. A

i7 represents wire-mesh trays or baskets for holding the nitrocellulose, the said trays being of such size that when inserted in the oven, as shown in the drawings, there will be a circulating-space between the said trays and the oven-wall, and said trays are furnished. with handles 18 to hold the trays a suitable distance apart and provide Pa circulatingspace between them for the purpose of convenience in handling. These trays are preferably mounted on small truck-wheels 1 9, which travel on the tracks 20, located at each side of the bottom oi' the oven, so 'thatP the trays may be readily carried in and out of said oven. l

In using the apparatus just described to carry out my process the trays 17 are filled with nitrocellulose '2l which has been dehydrated by any wet process, preferably by iny centrifugal wringer process hereinbet'ore mentioned, and which contains a certain percentage of liquid which is not in itself the solvent for nitrocellulose, in this caser alcohol being the liquid specified. 'lh'ese trays are TOO IIO

IIS

" or oven practically air-tight.

introduced into the evaporating-pan 8 fromr` the ether-tank 9, the amount used being indithen placed in the oven 1 and the door 15 thereofclosed, so as tokeep the compartment Ether is then cated by the gage-glass 13, thus enabling the operator to introduce a Sufficient quantity into the evaporating-pan to .colloid the nitrocellulose to the roper degree. Water is cir culated in the ollow walls of the oven to keep the oven atea suitable temperature to vaporize the ether without boiling, 'and as the ether evaporates and circulates in the oven it is readily absorbed by the wet nitrocellulose in the trays 17. When the proper amount of ether has been evaporated in the oven to colloid the mass of nitrocellulose, the

nitrocellulose is removed from the oven and may be pressedfdirectly into powder or may be first passed. through a screeningg ress or between a pair of rollers in order to end the mass and remove any lumps.

If it is desired to produce a granulated explosive for small-arms, the colloided material may be transferred to any suitable receptacle provided with a pro eller or movable arms and blades and rapid y agitated, which operation breaks the mass of colloided nitrocellulose into small grains or ranules, which are then removed to a suitable solvent-recovery ap aratus, the solvent recovered, the grains dried and sifted, when they will be found to form a smokeless powder of high quality.

I am aware of Letters Patents Nos. 430,212 and 436,898, granted to Hiram Stevens MaX- im, wherein a process isset out for colloiding nitrocellulose by subjecting it to vapor of a` solvent.. In these processes, however, the

nitrocellulose is used in a dry state and subJ jected to the solvent-vapor in a vacuum.

In my process, however, I use nitrocellulose 1n a wet state, as 1t absorbs the vapor more readily and evenly, and I do notv use the Vacuum. y

I have described my process particularly with reference to the process of subjecting alcoholized nitrocellulose to ether-vapor; but the method may be reversed that is, nitrof cellulose which is saturated with ether may be subjected to alcohol-vapor or other liquids may be employed without departing from the spirit of my invention.

W at I claim is- I1. The process of colloiding nitrocellulose which consists in mixing with the nitrocellulose a liquid which is not in itself a solvent of the nitrocellulose, then subjecting the wet nitrocellulose to a vapor which combines Awith the liquid in the nitrocellulose and 

